(function(jsonString) {
    var newString = jsonString.replace('warnWetter.loadWarnings(','');
    newString = newString.replace(');','');
    var newJSON = JSON.parse(newString);
    var jsonResult = "";
    if (newJSON.warnings.hasOwnProperty('906438999')) {
        jsonResult =JSON.stringify(newJSON.warnings['906438999'][0]);
    } else jsonResult = 'NULL'
    return jsonResult;
})(input)